ES2765451T3 - Light recycling for projectors with high dynamic range - Google Patents

Abstract

A projector display system (100) capable of recycling light from a plurality of light sources, said display system comprising: a plurality of partially coherent colored light sources (102), each emitting colored light for modulation; a light recycling module (103) including an integrator bar, said integrator bar configured to receive light from said light source at a proximal end and wherein said proximal end comprises a reflective surface, capable of reflecting light towards said integrator bar ; a first modulator, said first modulator comprising a plurality of movable mirrors, said plurality of movable mirrors that is capable of reflecting light received from said integrating bar in a first projection direction and a light recycling direction, wherein said direction of light recycling is substantially in the direction of the integrator bar; and a controller (116) configured to receive image and / or video input data, to send control signals to the first modulator, and to modulate the light source to adjust the intensity of the light source, the controller being configured to: - receive an input image; - calculate a mean level of the image for each modulated colored light; - determining the relative brightness increase by recycled light for each individual modulated colored light; and - reducing the intensity of the illumination of the colored light sources according to the inverse of the increase in relative brightness for the colored light.

Description

DESCRIPTION

Light recycling for high dynamic range projectors

Technical field

The present invention relates to light recycling for projector systems and, in particular, to systems and methods for High Dynamic Range (HDR) projector systems.

Background

Projector systems are being structured with improvements in dynamic range. Dual and multiple modulator projector display systems are known in the art. However, further improvements in both rendering and performance of such display systems are possible that are the result of improved modeling of light processing in such display systems. Furthermore, as appreciated by the inventors, it would be desirable to increase energy efficiency for single modulation display systems - in addition to dual / multiple modulation display systems.

The international search report issued in connection with this description cites the US Patent Application document. US 2008/246705 A1 (the "document '705"). The '705 document describes that in display systems employing spatial light modulators, light in the off state of the pixels in the off state of the space light modulator can be captured and directed back to the pixels of the space light modulator to recycle the light in the deactivated state in the display system. Another projector system is described in US7551341B1.

Compendium

Projection systems and / or methods for the efficient use of light are described by recycling part of the light energy for future use, as cited in the independent claims. Optional features thereof are cited in the dependent claims.

Other features and advantages of the present system are presented below in the detailed description when read in connection with the drawings presented within this application.

Brief description of the drawings

Examples of embodiments are illustrated in the figures referenced in the drawings. The embodiments and figures described herein are intended to be considered illustrative rather than restrictive. FIG. 1A depicts a dual modulator projector display system with a light recycling module shown schematically and as performed in accordance with the principles of the present application. FIG. 1C represents a projector display system comprising light recycling modules in a plurality of color channels.

FIG. 2 depicts an embodiment of a light recycling module that satisfies the purposes of the present application.

FIG. 3 shows the proximal end of an integrator bar for the purposes of the present application.

FIG. 4 depicts another embodiment of a dual / multiple modulator projector system in which it may be possible and / or desirable to perform light recycling in accordance with the principles of the present application.

FIG. 5 depicts yet another embodiment of a projector system in which light recycling may be possible and / or desirable in accordance with the principles of the present application.

FIGS. 6A and 6B represent many possible embodiments for projector systems that can provide these one or multiple opportunities for light recycling in accordance with the principles of the present application. FIG. 7A is a possible light recycling control system and / or a method for a single modulation projector display system.

FIGS. 7B and 7C represent the response curves and response table, respectively, for an individual modulated color response for a conventional DMD component.

FIG. 8 depicts another possible light recycling control system and / or method for a single modulating projector display system.

FIG. 9 depicts yet another possible light recycling control system and / or method for a single modulating projector display system.

FIG. 10 represents a possible response table for a light recycle for a given lighting pattern.

FIGS. 11, 12, and 13 represent three algorithms for effective light recycling in a display system for which light recycling is possible.

FIG. 14 depicts an alternative embodiment of a light recycling module in a dual modulator display system.

Detailed description

As used herein, the terms "component", "system", "interface", and the like are intended to refer to an entity related to a computer, be it hardware, software (eg, running) , and / or firmware. For example, a component can be a process that runs on a processor, a processor, an object, an executable, a program, and / or a computer. By way of illustration, both an application running on a server and the server can be a component. One or more components can reside within a process and a component can be located on one computer and / or distributed between two or more computers. A component may also be intended to refer to a communications-related entity, be it hardware, software (eg, running), and / or firmware, and may further comprise enough wired or wireless hardware to participate in the comunications.

Throughout the following description, specific details are set forth to provide a more comprehensive understanding for those skilled in the art. However, the well-known elements may not have been shown or described in detail to avoid complicating the description. Accordingly, the description and drawings are to be considered in an illustrative sense, rather than in a restrictive sense.

Introduction

In the field of projectors and other display systems, it is desirable to improve both image rendering performance and system efficiency. Various embodiments of the present application describe systems, methods and techniques that affect these improvements employing light field modeling for dual or multiple modulation display systems. In one embodiment, light source models are developed and used for an advantageous effect. The images displayed from camera images that make up the known input images can be evaluated to improve light patterns. In some embodiments, an iterative process can accumulate improvements. In some embodiments, these techniques can be used on moving images to make adjustments in real time to improve image rendering performance.

Dual modulation projector and display systems have been described in common property patents and patent applications, including:

(1) US Patent Number 8,125,702 to Ward et al., Issued on February 28, 2012 and titled "SERIAL MODULATION DISPLAY HAVING BINARY LIGHT MODULATION STAGE";

(2) United States Patent Publication No. 20130148037 to Whitehead et al., Published June 13, 2013 and titled "PROJECTION DISPLAYS";

(3) United States Patent Publication No. 20110227900 to Wallener, published on September 22, 2011 and titled "CUSTOM PSFs USING CLUSTERED LIGHT SOURCES";

(4) United States Patent Publication No. 20130106923 to Shields et al., Published May 2, 2013 and titled "SYSTEMS AND METHODS FOR ACCURATELY REPRESENTING HIGH CONTRAST IMAGERY ON HIGH DYNAMIC RANGE DISPLAY SYSTEMS";

(5) United States Patent Publication No. 20110279749 by Erinjippurath et al., Published on November 17, 2011 and titled “HIGH DYNAMIC RANGE DISPLAYS USING FILTERLESS LCD (S) FOR INCREASING CONTRAST AND RESOLUTION” and

(6) United States Patent Publication No. 20120133689 to Kwong, published on May 31, 2012 and titled "REFLECTORS WITH SPATIALLY VARYING REFLECTANCE / ABSORPTION GRADIENTS FOR COLOR AND LUMINANCE COMPENSATION".

An example of physical architecture

In general, a projector with a single Digital Micro Mirror Device (DMD) may have a tendency to have a limited contrast ratio. To obtain a higher contrast ratio, two or more DMDs and / or other reflectors (eg MEMS) can be arranged in series. Because a DMD can function as a time division or pulse width modulator, the operation of two or more DMDs and / or reflectors in series - both acting as pulse width modulators - tends to require division alignment. accurate timing and pixel-by-pixel correspondence of time division sequencing. Sayings Alignment and matching requirements can be difficult in practice. Therefore, in many embodiments of the present application, display systems and / or projectors can employ different dual modulation schemes to influence desired performance.

Simply by way of example, one embodiment of a projector display system may use the first modulator (eg, a first DMD / reflector) as a "premodulator" or "premod" - which can spatially modulate a light source using a halftone image that can be maintained for a desired period of time (eg, a frame or part of it). This halftone image can be blurred to create a spatially narrow bandwidth light field that can be applied to a second DMD / reflector. The second DMD / reflector - called the primary modulator - can pulse width modulate the blurred light field. This provision may tend to avoid both requirements mentioned above - p. For example, precise alignment by time division and / or pixel-by-pixel correspondence. In some embodiments, the two or more DMDs / reflectors can be frame-aligned over time, and frame-aligned spatially approximately. In some embodiments, the diffused light field of the premod DMD / reflector can substantially overlap the primary DMD / reflector. In other embodiments, spatial alignment may be known and taken into account - eg, to aid in image rendering performance.

Although the present application is presented in the context of a multiple, dual modulation projection system, it should be appreciated that the techniques and methods of the present application will find application in single modulation display systems, or other modulation display systems. dual, multiple. For example, a dual modulation display system comprising a backlight, a first modulator (eg, LCD or the like), and a second modulator (eg, the LCD or the like) may employ suitable optical blur components. and image processing methods and techniques that affect the performance and efficiencies discussed herein in the context of projection systems.

It should also be appreciated that - even though FIG. 1A represents a dual or two stage modulator display system - the methods and techniques of the present application may also find application in a display system with only one modulator or in display systems with three or more modulators (display systems with multiple modulator). The scope of the present application encompasses these various alternative embodiments.

FIG. 1A shows a possible embodiment of a dual / multiple modulator projector display system 100 that can satisfy the purposes of the present application. The projector system 100 employs a light source 102 that provides the projector system with a desired illumination such that a final projected image will be bright enough for the intended viewers of the projected image. Light source 102 may comprise any suitable possible light source - including, but not limited to: a Xenon lamp, laser or lasers, a coherent light source, partially coherent light sources. Because the light source consumes significant electricity and / or energy for the entire projector system, it is desirable to advantageously use and / or reuse light to conserve electricity and / or energy during the course of its operation.

Light 104 can illuminate a first modulator 106 that can, in turn, illuminate a second modulator 110, through a set of optional optical components 108. The light from the second modulator 110 can be projected by a projection lens 112 (or other suitable optical components) to form a final image projected onto a screen 114. The first and second modulators can be controlled by a controller 116 - which can receive image and / or video input data. Controller 116 may perform certain image processing algorithms, range mapping algorithms, or other such suitable processing on the image / video input data and control / output data signals to a first and a second modulator to achieve a projected final image 114. In addition, in some projector systems, it may be possible, depending on the light source, to modulate light source 102 (control line not shown) to achieve additional image quality control of the projected final image. .

The light recycling module 103 is depicted in FIG. 1A as a dotted box that can be located in the light path from light source 102 to first modulator 106, as will be discussed later. Although the present discussion will be provided in the context of this positioning, it should be appreciated that light recycling can be introduced into the project system at various points in the projector system. For example, light recycling can be located between the first and second modulators. In addition, the light recycle can be located at more than one point in the optical path of the display system. Although such embodiments may be more costly due to an increase in the number of components, that increase can be offset by saving energy costs as a result of multiple light recycling points.

FIG. 1B depicts an embodiment of a projector display system 100b comprising a simple modulator 106b. Light 102b is emitted (possibly under the control of the controller - not shown) and light beam 104b can be transmitted through a light recycling module 103b, as above. Modulator 106b can selectively reflect light, as desired by the controller - and modulated light 108b can be transmitted through projector optics 112b and projected onto screen 114 as a desired final image to be viewed.

FIG. 1C depicts an embodiment of a light recycling module that can perform light recycling on a plurality of color laser channels (eg, R, G, and B). As can be seen in this example, the display system may comprise a red light source (R) that is inserted into an integrating bar 126 (eg, 124 for B and 122 for G) that can be transmitted (possibly by reflectance). internal) to a controllable reflector 120 that may comprise one or more reflectors that can display a recycle position 120b or a transmit position 120a. If the light is to be recycled, the reflector 120b would reflect the laser light back toward the integrating bar 126 - which can be reflected within that path multiple times - until a command is given to the reflector (via controller, not shown) towards transmission position 120a. The light transmitted by the reflector 120a can be directed towards the red mirror 128 as shown. In the case of blue light, blue light can be combined with red light in a dichroic combiner 130. Similarly, green light can thereafter be combined as a dichroic combiner 132 and the light can then be further modulated and / or projected - as simply represented by optical element 120. It will be appreciated that this light recycling module can satisfy the purposes of single modulator, dual modulator and / or multiple modulator display systems, as desired.

A realization of light recycling

FIG 2 depicts an embodiment of a light recycling subsystem and / or module, as may be suitable for the purposes of the present application. As discussed above, this light recycling subsystem / module in the projector system can be located primarily between light source 102 and a first modulator 221. Light from light source 102 can be introduced into the optical path. through an integrating box / tube / bar 202 (eg, via port 201b, as seen in FIG. 3). The integrating box / tube / bar 202 may comprise a substantially reflected surface therein, such that light incident on its surface may be reflected (eg, possibly multiple times) until light exits its end 203 right distal. Once the light leaves the integrating box / tube / bar, the light can be placed on an optical path that is defined by a set of optical elements - eg, lenses 204, 214, and 216 and a set of filters and / or polarizers 208, 210 and 212.

The first modulator 221 may comprise a number of prisms 218a, 218b and a reflector 220. The reflector 220 may comprise a reflector DMD matrix, or a MEMS matrix - or any other suitable set of possible reflectors that can reflect light in at least two or more trajectories. Such a path is depicted in FIG. 2. As can be seen, reflectors 220 direct light onto prism interface 218a and 218b, such that light is thus reflected from lens assembly 222 and henceforth into a second modulator 229 ( eg, comprising a lens assembly 224, cores 226 and 230, and reflector 228). This light can be used to form the final projected image to be seen by an audience.

However, at a certain point during rendering of the projected final image, the full electricity / power of light source 102 may not be needed. If it is not possible to modulate the electricity from light source 102 (or if it is difficult or if there is an additional opportunity to conserve light), then it may be desired to recycle light from light source 102. In this case, and as can be seen in FIG. 2, it may be possible to align the reflector 220 from its current position as shown (i.e. where the light is directed to move to the second modulator) - to a position in place where the light would be reflected substantially back toward the integrator bar / tube / box 202, along substantially the same path as that described in moving in the right-to-left direction.

In another embodiment, a third (optional) path (not shown) allows the reflectors to direct the light from the light source to a light "discharge zone" - that is, a part of the projector system where the light is absorbed. light. In this case, the light is lost in the form of heat that is to be dissipated from the projector system. Thus, the projector system can have multiple degrees of freedom when it comes to directing light as desired.

FIG. 3 shows an embodiment of the proximal end 201 (ie, the end closest to the light source) which aids in influencing light recycling. As can be seen, the light can travel through the integrator bar / tube / box 202 (eg, by multiple reflections) back to the proximal end 201. The proximal end 201 may further comprise a rear portion 201a - which may further comprise a reflective surface - and a port opening 201b into which light from light source 102 may be introduced into the projector system. Light impacting on the rear 201a can be reflected back into the integrating bar 202 (possibly multiple times until the reflector or reflectors in the first modulator are directed to transmit light to a second modulator or some other suitable optical path to form the final image). The examples in FIGS. 2 and 3 can be considered an example of a light recycling module which (like other examples provided herein), is capable of recycling light at some point in the light path through the display system.

FIG. 14 is yet another embodiment of a light recycling module 1400 - which can be used for at least one laser and / or a partially coherent colored light source 1402, 1404, 1406. Light from such a source can be transmitted through a first optical subsystem 1408 to condition that light is introduced into integrating bar 1412 - which may comprise reflective proximal end 1410, such as in FIG. 3. A second optical 1414 subsystem can further condition the light as desired prior to its introduction on a first modulator 1416. As with FIGS. 2 and 3 above, this first phase of module 1400 may influence a recycle mode, as discussed.

After this first modulation, light can be transmitted through a third optical subsystem 1418 prior to being introduced into a second modulator 1420 - which modulates light for transmission through an optical projector subsystem 1422 to project a final image. for viewing.

Realizations about intense light

In one embodiment, a bright light modulator can affect adjustable lighting with a fraction of available light, unless combined with the pre-modulator. To accomplish this, both mechanical and / or non-mechanical subsystems and beam orientation techniques can be employed - eg, it may be possible to orient parts of the light source towards the various paths in the system using mechanical orientation, holograms with modulators light spatial or other spatial modulation methods. It may be desirable with such a system to increase efficiency by directing light where desired.

Mechanical beam orientation can utilize a collection of reflector elements that can be controlled over a range / range of motion in the horizontal and / or vertical direction. These reflector elements direct the light that reaches them to the desired areas of the modulators after the maximum brightness zone modulator creates non-uniform controlled lighting.

Non-mechanical beam-targeting methods can use a spatial light modulator to shift the uniform coherent light phase that reaches the modulator. Phase shifted light creates a three-dimensional light field when it is shaped as an image through a lens. The three-dimensional light field may be shaped as an image into a two-dimensional light field with different planes from the collapsed dimension images, with varying sharpness or PSF properties in one of the following modulators that create a two-dimensional light field.

Regardless of the way it is implemented, intense light modulation refers to using a modulator to direct the light that reaches it to any place in the subsequent modulators. Although there may be restrictions, such as range of positions and granularity, the term "anywhere" can still be used to distinguish bright light modulators from other modulators.

Depending on the number of high brightness modulation elements, PSF properties, and full coverage that can be achieved by the high brightness modulator, it may not be necessary in some embodiments to have a pre-modulator / first modulator between it and the primary modulator /second. In some embodiments, it may be possible that the intense light modulator may be of such performance that no modulation (pre or primary) is required after it.

Brightness modulator relay optics control to pre / primary modulator

In some embodiments, it may be possible to adjust the relay optics to control the forms of illumination of the spot scattering function in the pre-modulator / first modulator or primary / second modulator generated by a high brightness modulator. In some embodiments, there may be controls for adjusting the width dimension to half height (Full Width Half Max) in addition to controlling the shape or tails of PSFs. It may be desirable to predict, monitor and / or measure the resulting performance when light recycling is employed, as additional steps through the integrator bar will change the uniformity and angular diversity of the light, which in turn will affect the Resulting PSF.

Pre-Modulation / First Modulation Realizations

In some embodiments, the pre-mod / first modulation may involve the ability to modulate the light that reaches the pre-modulator on its way to the primary modulator. In some cases, pre-modulation can be used to increase the contrast of the system. With bright light, the bright light image may illuminate the pre-modulator in addition to lighting the non-image pre-modulator.

In some embodiments, a suitable pre-modulator / first modulator may be a DMD, LCD, LCoS, or other intensity modulator. Regardless of implementation, pre-modulation can be used to modulate the intensity of light reaching it in the following modulators. Each of the pre modulator elements (eg, mirrors, pixels, etc.) influences a fixed location on the following modulators, or on the screen if there is no additional modulation following the pre-modulator. Depending on the number of pre-modulation elements, the PSF properties and the total coverage that can be achieved by a pre-modulator, it may not be necessary for a primary modulator to follow next. It is possible that the pre modulator could be of such performance that no modulation (eg, bright or primary) is required before or after it.

Modulator relay optics control prior to primary

This section refers to the ability to adjust the relay optics to control the forms of spot scatter function illumination in the primary modulator generated by the Brightness Modulator or Pre-Modulator. There are controls to adjust the width dimension at half height as well as controlling the shape or tails of the PSFs. Recycling can be used with the pre-modulator, and it may be desirable to monitor, predict, and / or measure the resulting illumination intensity, as additional steps through the integrator bar will change the uniformity and angular diversity of the light, resulting in which in turn will affect the resulting PSFs.

Embodiments of the primary modulator

Primary / second modulation may involve the ability to modulate light that reaches the primary modulator on its way to the screen. In some embodiments, this may tend to ensure a quality image resulting in high contrast, and a desired intensity and spatial resolution. In some embodiments, it may be possible that bright images and / or the pre-modulator may illuminate the primary modulator in addition to illumination of the primary non-image modulator.

In some embodiments, a suitable primary / second modulator may be a DMD, LCD, LCoS, or other intensity modulator. Regardless of the way of implementation, the primary / second modulation can be used to modulate the intensity of the light that reaches it in the following modulators. Each of the elements of the primary modulator (eg, mirrors, pixels, etc.) influences a fixed location on the screen. The size and shape of each location should be consistent to form the projected image on the screen whose overall size and shape will be determined by the projection lens. Depending on the contrast range of the primary modulator, it may not be necessary to use a high brightness modulator or pre-modulator. It is possible that the primary modulator may be of such performance that no modulation (high or high brightness) is required before it. It may be possible to use recycling with the primary modulator. It would be desirable to understand the resulting illumination intensity, both in level and over time to compensate with an illumination adjustment or by changing the modulator signal to ensure that the desired image is formed. It is possible to measure this level. It is also possible to model and predict this level using algorithms.

Other Projector System Embodiments

FIG. 4 depicts another embodiment of a dual / multiple modulator projector system 400 in which it may be possible and / or desirable to perform light recycling. As can be seen, projector system 400 may comprise one or more light sources (eg, 402a and / or 402b, or other additional light sources). In this embodiment, light source 402a provides light in an integrated subsystem / box 404a that may resemble the embodiment of FIG. 2A. The light from 402a can finally reach the first modulator 406 - where the first modulator 406 can be constructed in substantially the same manner as FIGS. 1A, 1B, 1C, and / or 2 (that is, with reflectors that can reflect light back to the subsystem / integrating box 404a. The light can continue to subsystem 408 optical, the second modulator 410, and thereafter to the projector lens 412 and a projected final image can be formed on screen 414.

However, another opportunity for light recycling may occur with another one (or more, in other embodiments) light source 402b. In one embodiment, light source 402b can be used as another primary light source (ie, to provide a significant amount of light for final images, a substantial amount of time). In this embodiment, light 402b can be further reflected by reflector 403 such that this light can be combined with light 402a in beam splitter 405 - and the combined beam forms the final image a substantial amount of time.

In another embodiment the light source 402b can be used for a shorter amount of time to provide bright illumination of part of the image. It should be appreciated that reflector 403 may be a single mirror that can be moved (eg, to bring light to a discharge area or other recycling subsystem). Alternatively, reflector 403 may be a set and / or array of reflectors (eg, MEMS, DMD, or the like) to provide finer control of additional light from 402b.

In yet another embodiment, light source 402b may be optional and integrating box / subsystem 404b may have a fully reflective surface at the proximal end with respect to where light source 402b would be. In this embodiment, the light may have another path (eg, inside box 404b, in addition to box 404a) in which to recycle light. In another embodiment, it might be possible to use a one-way mirror for 405. In this case, reflector 403 would simply be a controllable mirror that can redirect light toward 404b, and thus reflector 403 may only be necessary to “fold” the recycling system. In such an embodiment, there may be no need to have a recycled light at 404a but instead the light may be recycled at 404. This may be desirable as the recycling reflector, which may not have a hole in it. the same for the entrance of light, making it a much more efficient recycler.

FIG. 5 is yet another embodiment for which light recycling may be possible and / or desirable. System 500 may comprise a light source 502 and an integrating subsystem / box 504 as previously described. Polarizer 505 may be a controllable polarizer such as an LCD that will polarize a selectable portion of the light in one orientation. Splitter 506 may be a polarizing beam splitter that will directly pass the light in an orientation such as a field of uniform light 514 to be combined using 516 in the primary modulator 518. The polarized light in the other orientation is redirected by 506 as 508. Mirror 510 can be a mirror to fold the system and bring the light to a pre-modulator or to a modulator 512 of intense luminosity, depending on the design of the system.

The 512 non-uniform light field is then combined with 514 using 516 to illuminate 518. When 512 is a pre-modulator, beam 514 can be used to provide some basic level of illumination less than the 512 first stage without darkness to very dark parts of image 522. Alternatively, when 512 is a strong light modulator, 514 is used to provide the uniform light level required by image 522 in regions where there will be no light in the light field non-uniform created by 512.

In other embodiments, it may be possible to place a recycle type integrator bar (similar to those described in FIG. 3), between 510 and 512 (or between 506 and 510), and a non-recycle version of an integrator bar ( eg, without a rear reflector) between 506 and 516. In such an embodiment, it may be desired to remove 504 after 502 to maintain light as a narrow beam.

A schematic embodiment

FIGS. 6A and 6B schematically represent one or more possible embodiments for projector systems that these multiple opportunities for light recycling can afford. FIG. 6A schematically represents the 600 processing that may be possible with a dual / multiple modulator projector system. This processing may include light from a variety of coherent or partially coherent laser light sources - eg, where the laser light may be pulsed (602) or supplied by laser diodes 604. Such light can be combined and transported (606) in a variety of architectures and manners (as described in connection with various of the above embodiments). The light can then be divided (608) into its components (eg, 610 to 620) and this light can be combined and divided (622) to fulfill various functions, such as bright light (628), lighting (630) discharge, pre-mod (or first modulator) lighting (626) and primary (or second modulator) lighting (624).

In one embodiment, adjusting the laser power to affect the entire viewing area uniformly for overall attenuation. This may be appropriate for some images and scenes in projector systems where it is possible to adjust the laser power and / or the power source. However, in some circumstances, it may be advantageous at low luminance levels to apply uniform illumination with a controllable base level directly to the high brightness modulators, pre-modulator / first modulator or primary / second modulator. Controlling this type of laser power adjustment will be considered another form of global attenuation. In an embodiment that employs multiple laser sources (either an individual laser or a group of lasers for each controllable source, or by dividing the lasers or laser groups on each controllable source) in the display system, it may be possible arrange them spatially in such a way that each one affects a part of the viewing area allowing local attenuation. This method is different from the high brightness modulator in that these local dimming areas are spatially fixed, where the local dimming areas by high light modulation can be spatially adjustable. It is possible to use the mechanical orientation of the light to control the adjustment of the laser power to each zone by directing the light that reaches the mirror towards a predetermined spatial zone in the modulator.

In such a case, the mechanical light-orientation device can be considered part of the laser power setting and not a bright light modulator and / or pre-modulator, however these systems in which the number of elements individually Controllable in mechanical orientation is greater than the number of spatial zones, they have the additional advantage of being able to spatially redistribute lighting from a fixed or variable source, rather than having to directly vary the source of each zone. The spatial application of laser lighting to modulators can be controlled by lighting optics for each modulator. For global dimming, illumination through illumination optics (eg, lenses, integrator bars, etc.) can be designed to illuminate the modulator evenly. For local dimming, illumination using illumination optics (eg, small lens arrays, segmented integrator bars, etc.) can each be designed to take a light path and spread it across a desired part of the modulator to create the proper PSF.

In an embodiment where the pre-modulator / first modulator is anticipated to receive most of the illumination, if light recycling is implemented, then it may be desirable for the illumination to be adjustable, either in the split or with the laser power control, or using modulators to compensate, which can reduce contrast.

Various schematic embodiments

FIG. 6B schematically represents various embodiments of projector systems that may affect such processing, as indicated in FIG. 6A. The system 632 may optionally provide for bright illumination 628 to enter an optical path 634 towards a light modulator 636 intense. This light can be sent either to the light path of the pre-modulator (or first modulator) at 642 through optical path 644 - or the light can be discharged (638) and possibly recycled at 640. The phase of the pre-modulator / first modulator can introduce light into 626 through optical path 652. The light can be combined with bright illumination on the pre-modulator / first modulator 646, as described. The light can either be sent to the primary / second modulator (eg, forming a 654 image of the pre-modulator) - or it can be downloaded and recycled at 648.

The primary / second modulator (660) may receive light from the pre-modulator / first modulator or primary illumination 624 (eg, via optical paths 656, 658 respectively). The light can be sent as a primary image 662 to the projection optics 664, forming an image 666 projected onto a projection screen 668 (possibly vibrating if the light source is coherent or partially coherent) and displayed in an auditorium 670 or Similary. Otherwise the light can be downloaded and recycled at 674.

It will be appreciated that this schematic diagram can support a variety of possible projector systems and that they are all included in the scope of the present application. It may be sufficient that the architecture of a projector system can support one or more opportunities for light recycling for the purpose of the present application.

Control algorithm embodiments

As mentioned, on many occasions during the projection of an image, a set of images or a video, it may not be desired to use the full power of the light source to form the final projected image. In this case, a part of the light can be recycled many times (substantially indefinitely), until a brighter image needs to be formed. Furthermore, since reflector 220 may actually comprise a set (or array) of reflectors, the opportunity to recycle light may be possible based on local dimming. In a possible embodiment, it may be possible to employ light recycling - based on either global or local dimming - when not all available light is needed to form the final projected image - and then use it solely on the basis of a stated goal eg projecting "bright light" onto the final projected image. Intense luminosity can be a part of the image for which you want to direct a good amount of energy more luminous than its surrounding part of the image to accentuate that part.

In another embodiment, it may be possible to employ light recycling - again based on either global or local dimming - to enhance the luminance of an image or scene, i.e., on average, a brighter image or scene than the one before it. These opportunities may arise during illumination of the pre-modulator / first modulator phase, or primary / second modulator phase - as seen in FIG. 6B.

In one embodiment, the projector system can make a determination of how best to use light recycling through the controller as it processes the image / video input data. The decision to recycle can be made either on the fly, as the image data is processed - or in advance, in advance using a plot, frameset, or scene-by-scene approach. In another embodiment, a full video and / or offline scenes can be analyzed and the control signals can be sent to the controller as part of a stream of associated metadata, along with the image / video data.

FIG. 7A is an embodiment of a flow chart for performing light recycling. The control method / system 700 can input image data at 702. Based on the curve and / or response table (eg, as shown in FIG. 7B), the system / method can calculate the average image level (APL) for each individually modulated color (IMC) of the modulator. As can be seen in the graph of FIG. 7B, each individual color may display a different relative brightness for a given DMD fill percentage. It may be desirable to take these color differences into account when performing light recycling - to remove and / or mitigate any tonal visual artifacts. It should be appreciated that the flow charts in FIGS. 7A and 8 can assume that recycling generates a uniform light field - while the flowchart in FIG. 9 can anticipate a spatial intensity variation due to recycling and use the tables of FIGS. 7C and 10. For example, according to the Table represented in FIG: 7C, an input image can be divided into a 5 x 4 matrix of image regions, and light recycling in each of the image regions it can be adjusted, as noted, from 0% to 40%.

Returning to FIG 7A, at 706, the system / method can determine the relative brightness increase for each BMI. Once this has been achieved, the system / method can instruct the display system to reduce the intensity of the light source in reverse of the increase in brightness for each BMI. It should be appreciated that other functional relationships may be possible and / or desirable between the intensity of the light source and the increase in brightness - eg, possibly some inverse relationship of some brightness increase function. When the term "reverse" is used herein, it should be appreciated that other such embodiments are also possible. It is possible to adjust the intensity of the light source to 708, but in some embodiments, the recycling may remain the same (eg, the percentage of recycling may not change due to reduction of the source, only the absolute value - not putting too much light on the modulator). Because light moves quickly and even the fastest PWM cycle is comparatively very slow, recycling can be considered instantaneous and the resulting illumination level can be achieved right after the modulator is switched to its current state.

In the case where the system employs DMDs as primary modulators (eg, modulators that can extend modulation over various time slots), there may be a modulator status and resulting recycle level for each time slot and each one can be calculated and compensated. For systems that employ DMD as pre-modulators, there can be only one time slot, as the system can lead them to a binary halftone pattern - which can change only by frame (eg, in practice you can change it 1-4 times per frame, but this may be significantly less than the 10's-100's of time slots for a primary DMD modulator). With embodiments that employ LCD and LCoS as primary modulators, they can switch slowly (relative to DMDs) while visualization occurs - so that the resulting recycle can be integrated at that time to determine how to compensate.

While the control method / system of FIG. 7A can work in general for any dual / multiple modulator display system, this control can also work in the context of a single modulator projector system (eg, which would be built in the same or similar way to FIG. 1B). Recycling in the primary modulator can come from the time sequential nature of DMD, LCoS and LCD based systems.

FIG. 8 is yet another control system / method (800) for light recycling. Control can start by inputting image data into 802. At 804, the system can calculate the APL for each IMC. The system can then determine the relative brightness increase for each BMI at 806. At 808, the system can reduce the intensity of the light source to the closest inverse of the increase in brightness for each BMI, possibly without going below of that inverse value. In one embodiment, it can be assumed that the system can reduce the light with the modulator but not increase it - in which case, it may not be desired that the system can reduce the light source to below the required level. However, in another embodiment (eg, in the case of a mostly dark modulator image), the opposite may tend to be true (eg, the system may reduce illumination and then adjust the modulator to allow pass more light). In such a case, step 808 can proceed to reduce the intensity of the light source to the closest inverse of the increase in brightness for each BMI and still allow modulator compensation.

The system at 810 can then reduce the intensity of the image driven to the modulator to compensate for the difference between the desired inverse of the brightness increase and the adjustment that can be obtained with the light source. Alternatively, step 810 may also adjust the intensity of the image driven to the modulator to compensate for the difference between the desired inverse of the brightness increase and the adjustment that can be obtained with the light source.

Fig. 9 is yet another embodiment of a control system / method for light recycling. However, this control system / method may work well in display systems where light non-uniformity may need to be considered and / or adjusted due to recycling, and lighting intensity control is high definition or continuous. . The system / method 900 can input image data at 902. At 904, the system can calculate the APL for each region of a BMI (ie where the image can be divided into different regions). In 906, the system can determine the relative brightness increase for each region in each BMI based on the experimental statistics. The system can output patterns (eg, certain regions disabled (OFF) while the rest are enabled (ON)) to the modulator, and observe the light distribution. Depending on the location of the dark region, your recycled light may return to the modulator unevenly. This non-uniformity needs to be compensated for in the modulator.

In 908, the system can reduce the intensity of the light source in reverse of the region with the least increase in brightness for each BMI. The system can determine the relative brightness increase for each region in each BMI, based on adjusting the intensity of the light source. Next, at 912, the system can reduce the intensity of the image driven to each region of the modulator to compensate for the difference between the desired inverse of the brightness increase for that region and the adjustment of the light source.

Given an input image divided into a 5x4 matrix of image regions, FIG. 10 represents an example of a partially complete Table (eg, the center and corner values are complete only in measurement, estimation and / or calculation - the rest can be filled in similarly), to establish non-uniform levels of recycling of light in the modulator, given a certain pattern of modulator regions (eg, as derived as part of experimental statistics). In another aspect, it may be possible to display a pattern and then adjust the resulting recycling levels based on its characteristics. For example, Table 1 shows the luminance characteristics of a segmented image in a 3 x 3 matrix of image regions (eg, in each region, shows whether the average or peak luminance level is above or below a predefined luminance threshold (eg, 10 nits)). For example, because the lower right region is OFF (or below the threshold), in one embodiment, as shown in Table 2, most of the light recycling can be done closer to that area and then go down to get to images positioned in more distant areas. Many of these tables, obtained by experimentation, can be used in 906.

Table 1 - Luminance characteristics of a segmented test image in the form of a 3x3 matrix of image regions

Table 2 - Light recycling percentage for a 3x3 segmented image based on image characteristics

FIG. 11 is an embodiment of an algorithm (1100) for reducing the intensity of the light source in accordance with the increase in brightness. Such an increase in brightness may occur based on individually modulated color in some systems.

At 1102, the system can input a desired image for viewing. At 1104, the system can calculate the desired (or otherwise required) light field to be generated by the pre-modulator for each of the individually modulated colors (IMC). At 1106, the system can calculate the average image level (APL) for the pre-modulator of each BMI. The relative brightness increase can be determined at 1108 for each of the BMIs in your APL. At 1110, the system can then reduce the intensity of the light source in reverse of the increase in brightness for each BMI.

FIG. 12 is an embodiment of an algorithm (1200) for reducing the intensity of the light source - especially in systems that can employ polarization in projected images - eg, as seen in FIG. 5.

At 1202, the system can enter a desired image for viewing. At 1204, the system can calculate the amount of light to be diverted directly to the primary modulator (eg, such as 514 in FIG. 5), possibly for each of the BMIs. At 1206, the system can then calculate the light field that needs to be generated by the pre-modulator of each IMC. The APL can then be calculated for the pre-modulator of each BMI at 1208. The system can then determine the relative brightness increase for each BMI based on its APL at 1210. At 1212, the system can reduce the intensity of the source of illumination in reverse of the brightness increase for each BMI. This can also include the amount of light that is to be diverted directly to the primary modulator for each BMI. In 1214, the system can then adjust the polarizer (eg, 505) to align the polarization in a beamsplitter (eg, 506) such that a desired amount of light can be deflected directly into the primary modulator.

FIG. 13 is an embodiment of an algorithm (1300) that can input images that were generated without the assumption that the display system can participate in light recycling. In one embodiment, the system can be adjusted for light recycling in many possible ways - eg, take a higher-grade "EDR" and map it to adopt the capabilities of the target display, while retaining the artistic intention as metadata.

At 1302, the system can input a desired image for viewing. This image may have been created without assuming that no recycling will / will be achieved. In 1304, the system can calculate the APL for each BMI. At 1306, the system can determine the relative brightness increase for each BMI based on its APL. The system can then provide (or otherwise calculate) the brightness range that can be achieved for each BMI to the display management algorithm at 1308. At 1310, the display management algorithm can generate an image to be displayed at based on a recycling range that may be less brilliant than can be achieved for each BMI with recycling - but possibly not greater. In 1312, the system can then calculate a new APL (NAPL) for each BMI. In 1314, the system can determine the new relative brightness increase for each BMI based on its NAPL. Thereafter, the system can, in 1316, reduce the intensity of the light source in reverse of the NAPL for each BMI.

A detailed description of one or more embodiments of the invention has now been provided, read in conjunction with the accompanying figures, illustrating the principles of the invention. It is to be appreciated that the invention is described in connection with such embodiments, but the invention is not limited to any embodiment. The scope of the invention is limited only by the claims and the invention encompasses numerous alternatives, modifications and equivalents. Numerous specific details have been set forth in this description to provide a thorough understanding of the invention. These details are provided for the purpose of Example and the invention can be practiced according to the claims without some or all of these specific details. For reasons of clarity, the technical material that is known in the technical fields related to the invention has not been described in detail so that the invention is not unnecessarily complicated.

Claims (15)

1. A projector display system (100) capable of recycling light from a plurality of light sources, said display system comprising: a plurality of partially coherent colored light sources (102), each emitting colored light for modulation; a light recycling module (103) including an integrator bar, said integrator bar configured to receive light from said light source at a proximal end and wherein said proximal end comprises a reflective surface, capable of reflecting light towards said integrator bar ; a first modulator, said first modulator comprising a plurality of moving mirrors, said plurality of moving mirrors that is capable of reflecting light received from said integrating bar in a first projection direction and a light recycling direction, wherein said direction of light recycling is substantially in the direction of the integrator bar; and a controller (116) configured to receive image and / or video input data, to send control signals to the first modulator and to modulate the light source to adjust the intensity of the light source, the controller being configured to: - receive an input image; - calculate an average image level for each modulated colored light; - determine the relative brightness increase by recycled light for each individual modulated colored light; and - reduce the intensity of illumination of colored light sources in accordance with the inverse of the relative brightness increase for colored light. 2. The projector display system according to claim 1, wherein said light source is one of a group, said group comprising: laser, partially coherent light, partially coherent colored light, LED, xenon lamp. The projection display system according to claim 1, wherein said projection display system further comprises: a second modulator, said second modulator being able to modulate the light received from said first modulator in the first projection direction and transmitting said modulated light for projection. The projection display system according to claim 3, wherein said first modulator comprises a pre-modulator, and optionally wherein said pre-modulator is capable of producing a halftone image of an image that is desired to be displayed. . 5. The projection display system according to claim 4, wherein said second modulator comprises a primary modulator, and optionally wherein said primary modulator is capable of pulse width modulation of said halftone image produced by said pre-modulator. modulator. 6. The projector display system according to claim 1, wherein said first modulator comprises a high brightness modulator. The projector display system according to claim 6, wherein said intense light modulator is capable of locating additional light energy in a main light beam to brightly illuminate a desired part of an image to be displayed, and optionally where said second modulator is capable of modulating said main beam and said additional light energy to produce a desired image. 8. The projector display system according to claim 1, wherein said light source comprises a plurality of colored light sources; and for each colored light source, an integrator bar, said integrator bar configured to receive light from said light source at a proximal end and wherein the proximal end comprises a reflective surface, capable of reflecting light back to said tool bar; and for each colored light source, a modulator, said modulator comprising a moving mirror, said moving mirror capable of reflecting the light received from said integrating bar in at least one projection direction and a light recycling direction where said recycling direction of light is substantially in the direction of the integrator bar. 9. The projector display system according to claim 8, wherein said projector display system further comprises: a dichroic combiner, said combiner capable of combining at least two colored light beams from at least two integrating bars to form a main light beam. 10. A method (700) for recycling light in a projector display system, the display system comprising a plurality of partially coherent colored light sources, each emitting colored light for modulation, a first modulator comprising a plurality of moving mirrors, and a light recycling module; where the method comprises: receiving (702) an input image; calculating (704) an average image level for each individual modulated colored light; determining (706) the relative brightness increase by recycled light for each individual modulated colored light; and reduce (708) the intensity of illumination of colored light sources according to the inverse of the relative brightness increase for colored light. 11. The method according to claim 10, wherein the method further comprises one of: reducing the image intensity of a control signal fed to the modulator to compensate for the difference between the inverse of the brightness increase and the adjustment that can be obtained with the light source; or adjust the non-uniformity of recycling, when determining the relative brightness increase, to compensate for the non-uniformity of light recycling. 12. The method according to claim 10, wherein the display system further comprises a second modulator, the second modulator receiving light from said first modulator, and the method further comprises: adjusting the image of a control signal driven to the second modulator in based on the increase in brightness by recycled light for the first modulator. 13. The method according to claim 12, wherein adjusting the image of the control signal led to the second modulator comprises: Reduce the image intensity of the control signal fed to the second modulator based on a functional relationship between the increased brightness and the adjustment that can be obtained with the light source. 14. The method according to claim 13, wherein the functional relationship is substantially an inverse relationship. 15. The method according to claim 12, wherein the method further comprises one of: adjust the non-uniformity of light recycling, when determining the relative brightness increase, to compensate for the non-uniformity of light recycling; or calculate the brightness adjustment of the source by including the light diverted to the first modulator as a primary modulator.